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Why 'leap' when we just add?

| February 28, 2012 8:15 PM

"Leap" is a lot easier to say than are bisextile and intercalary, a.k.a. Feb. 29. Still, I've never understood why we say "leap," implying something skipped over, when we're adding a day. So I began a look at leap year 2012 with etymology (no surprise to regular readers), which usually means Latin. Gotta love those ancient Romans.

Bisextile - bissextus in Latin - means literally, the "twice sixth day," as in the sixth day before the Calends of March, or about Feb. 24. A calends is the first day of a new moon and thus a new month. Calendars and time were originally based on astronomy and later changed in much of the Western world by a pope, pushing conversions to Christianity by changing the calendar to coincide with religious dates (or changing the dates, including Christ's birthday Jan. 6, to coincide with pagan/other holidays). Can't credit Pope Gregory with leap year, though; Julius Caesar did it first in 45 B.C.

Turning to intercalary, or intercalarius, "inter" means among, and "calo," to call out or proclaim. The verb intercalare in Italian means to insert; intercalare is also a Latin conjugation of intercalo, meaning roughly the same thing. (My apologies to Latin teachers for generalizing; it is a complex language, but so vital to our own that I had to try.)

So why did Caesar (and now, why do we) insert a day before March at all, and why every four years? Back to the artificially imposed calendar: Switching it away from astronomy means counting time a little differently than it actually passes (assuming we define time by the passing of natural events). Give it long enough and a slight difference becomes too far out of sync with reality.

And how did we get from "insert" to "leap?" Back to Julius and Gregory. Caesar formed a 12-month, 365-day calendar and added the bisextile day every four years. That made the year 11 minutes and 14 seconds too long. Fifteen centuries of that overage exceeded 16,000 minutes, so the Gregorian calendar skipped Caesar's last day in February, but still included it every four years.

That still puts things off, but by a lot less. Our calendar years now average 365.2425 days; the solar year is 365.242216 days. It will take more than 3,000 years before the Gregorian/our calendar will gain an extra day in error.

Marking time exists to serve society and societies have evolving needs and desires. While virtually everyone sticks to this Gregorian calendar at least for commerce, in some Eastern cultures such as Chinese and Hebrew, people use a lunisolar calendar to mark time and important events. The U.S. use of the Gregorian calendar was inherited; it derives from the U.K. parliament's adoption in 1751 (extending to the colonies). Adopting it there and in other countries came with violent resistance. Time is precious, even sacred.

Thursday: A brief look at the history of time.

Sholeh Patrick is a columnist for the Hagadone News Network. Contact her at sholehjo@hotmail.com.